Stacking macro images

[BAB]

I'm shooting diamond rings and the clarity of the diamonds are sometimes mottled depending on the angle of the stones with numerous stacks like 26
I have currently just finished shooting some stacks of only 10-12 images and they are much better.
Here are the approximate details
Lens 120 mm macro with 52 mm tube and 1,7extender appx 30 stacked images of a 25 mm high object
Lens 120 mm macro with 1.7x appx 24 stacked images
Lens 120 mm macro appx 12 images
Lens 13" from object except with the 120 mm macro alone I've back off just using a small part of the sensor
Problem stacking program results with some smudged areas in the higher magnification solutions with over 20 stacks
My goal to to print very large images a single ring would be about 13"" in diameter! I'm not sure how much of the sensor I can really use without compromising a fairly easy workflow.

H5d 50
120 mm macro ii
Zerene stacker
Focus adjusting internally with phocus software
1/500 @ f9,5 or f11
Foba stand
Mirror up
Capture with focus with 200 ms delay

Thanks

[DanielStone]

May I ask, why are you using an extender AND an extension tube?

I can understand the extension tube(s) for macro macro, but a tele-extender as well? Scratching my head here 

-Dan

[HarperPhotos]

Hello,

I have to agree with Daniel about the 1.7 extender.

This image below was taken with a Rodenstock 120mm Apo Rodagon lens on a Horseman VCC adaptor with a Mamiya 645 AFDII camera and a Leaf Aptus 75 back.

The F Stop was F11.0 and there was 15 images taken which where then focused stacked using Helicon Focus. I find Helicon Focus to be excellent.

With the bellow focusing of the Horseman VCC adaptor focus stacking is very smooth and easy to achieve.

Ciao

Simon

[BAB]

My reason is if you make an image of a person from 20 feet with a 50 mm lens that person fills  X part of the sensor making an image with the same distance using a 85 mm lens the person would fill more of the sensor.
Backing off with the camera and just the macro lens alone the image on the sensor is much smaller than with the extender. As I was experimenting I have tried many possible combinations to achieve the result I'm after.
I contacted Schneider tech support to inquire about there tilt shit lens and the engineer did a worksheet for me with an object that was 18mm x 25mm there lens would require at least 18 images to achieve sharp focus throughout.
I found backing off the camera from the object I was able to get sharp focus with fewer images, now I'm trying to also find the sweet spot to fill as much of the sensor as possible reducing the amount enlargement needed to print the file.
As canon makes a 180 mm macro and hasse does not the 180 macro allows for the situation I'm discussing . I hope the helps your itch!

[Bart_van_der_Wolf]

I'm shooting diamond rings and the clarity of the diamonds are sometimes mottled depending on the angle of the stones with numerous stacks like 26
I have currently just finished shooting some stacks of only 10-12 images and they are much better.

Hi,

It sounds like you first need to figure out some of the basics for Close-up Focus-stacking.

1. Get the (combination of available) optics that gives the highest individual image quality at the optimal aperture for the optics, and allows a decent size reproduction of the scene on the sensor area.
2. From that situation, determine the magnification factor. The magnification factor, image size on sensor divided by the original object size, allows to use much easier Depth of Field calculations.
3. Using that, calculate the Depth of Field for an individual image, and assume that the CoC parameter is equal to the sensel pitch of your camera/back.
4. Given that resulting DOF, calculate how many exposures are required to cover the full depth of your scene. Use that to shoot the focus slices and feed the images to Zerene Stacker or Helicon Focus.

Without getting the correct amount of images at the correct intervals, the rest becomes a software crap shoot ...

Then select the appropriate algorithm for the subject (some are better for surfaces, others are better for edges/occlusions), or use several and combine those. I assume you know how the software works.

Cheers,
Bart

[Louis Novak]

I agree with Bart, it sounds like you are not getting the right amount of images with the levels of focus to create a proper stack. Some objects will need a lot more captures than others, depending on the detail and parts on different planes of focus. I have done stacks of insects that required a couple hundred captures. When you work with stacking, any sort of vibration could potentially mess up the stack as well.

Also in Zerene Stacker you have the option of selecting different stacking methods, (PMax) is more resisting to blurring and halo.